Catherine Vogler and coworkers used sequences of the mitochondrial cytochrome oxidase subunit I gene from crown-of-thorns starfish samples covering its entire distribution to demonstrate that the species consists of four deeply diverged clades (from the Red Sea, Pacific Ocean, northern Indian Ocean and southern Indian Ocean respectively).

There are conservation implications to this discovery.

The outbreaks of the crown-of-thorns starfish in the Indian Ocean and the Red Sea do not appear to be as massive and widespread as in the Pacific, suggesting that outbreak patterns might vary between the different sibling species.